METHOD FOR THERMAL FUSION CONNECTION OF SYNTHETIC RESIN PIPE

PURPOSE:To obtain a uniform fusion state over the entire peripheral surface of a pipe by eliminating the protrusion of a molten resin when the pipe is connected to a socket, by thermally fusing the inner surface of a joint receiving opening and the outer surface of a pipe insert opening while the side surface of a washer shaped ring body is pressed to the end surface of the joint receiving opening through a two-split metal clamp jig. CONSTITUTION:A two-split metal clamp jig 3 is fixed to the outer surface of a pipe insert opening 1 at a position leaving an insert length (l) in a joint receiving opening and a washer shaped ring body 4, of which the inner diameter (d) is made slightly larger than the outer diameter R of the pine insert opening 1, is externally fitted to the outer surface of the pipe insert port from the pipe insert opening end 1. Subsequently, the resin of the surface layer parts of the outer surface of the pipe insert opening 1 and the inner surface of a joint receiving port 2 is melted under heating and the pipe insert opening is immediately inserted in the joint receiving opening 2. Next, the inner surface of the aforementioned joint receiving opening 2 and the outer surface of the aforementioned pipe insert opening 1 are thermally fused while the surface 4A of the washer shaped ring body 4 is pressed to the end surface 2' of the aforementioned joint receiving opening 2 through the aforementioned two-split metal clamp jig 3. At time of thermal fusion, the protrusion of the molten resin generated from the fusion interface of the outer surface of the pipe insert opening 1 and the inner surface of the joint receiving opening but blocked by the washer shaped ring body 4 to be brought to a pressure collapsed state.